http://www.detnews.com/apps/pbcs.dll...=2008808130352

sample quote

Eberspacher GmbH and its Novi-based North American subsidiary have developed technology that replaces a muffler with a speaker inserted into the exhaust system. That speaker -- a heat restraint version of a typical stereo speaker -- emits sound waves that can either silence engine noise or tune it so that even a quiet hybrid sedan can roar like a classic muscle car.

 

The day I see a Prius go by sounding like a big V8 I'm gonna go jump off a cliff

 

Cool idea but they should stick to using it to make the car quiet. Or maybe they could just use a regular muffler instead and keep the speakers on the inside of the car...now thats an idea!